Remember that we rely on very noisy abstractions in many sciences, and especially in biology, nutrition, and public health. In terms of the (abstract) model of calories-as-fuel, different sugars mostly all have the same effect of providing about 4 calories per gram. And in terms of the (abstract) model of glucose-as-blood sugar, they all get more or less converted to glucose eventually.

But behind those useful high level abstractions, these are all different molecules and bodies have different ways of processing them: different gut absorption and biome effects, different organs, different catalysts, different pathways, different rates of processing, etc.

So from certain views, yes, "sugar is sugar" but from other views each compound that we call sugar is a different molecule and this implies critical and sometimes quite impactful differences in how any body may respond to it at any given time.